HomeMy WebLinkAboutCP 94-02; Poinsettia Shores - Vistamar Area B-2; Partial Release of Rough Grading; 1997-06-17-
'PARTIAL RELEASE OF ROUGH GRADING
C.P. 94-02, DWG 352-4A
LOTS 1-16
CARLSBAD, CALIFORNIA L
WATT RESIDENTIAL PARTNERS
DBA WATT HOMES, SOUTHERN CALIFORNIA DIVISION
27720 JEFFEMON AVENUE, SUITE 200
TEMECULA, CALIFORNIA 92590
PHONE (909) 694-0870
FAX: (909) 694-1941
TABLE OF CONTENTS
1. 8% x 11 Plat (All Lots) -
- 2. Soils Report by GeoSoils, Inc.
- 3. Pad Certification - O'Day Consultants
4. Letter Requesting Release
5.
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Geotechnical Review - Pavement Design
(Refer to pages 19 and 20) -
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- 5741 Palmer Way - Carlsbad, California 9200
June 17,1997
W.O. 2198-B-SC
Watt Homes
27720 Jefferson Avenue, Suite 200
Temecula, California 92590
Attention:
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- Ms. Carrol Long, Mr. Jonathan Weldy
Subject: Interim Report of Rough Grading, Vistamar at San Pacifico, Area B-2,
Carlsbad, California
Dear Ms. Long and Mr. Weldy:
Grading and processing of original ground within the building pad area at the subject site
was observed and selectively tested by a representative of GeoSoils, Inc. (GSI) during the
earthwork phase of development for the subject site.
The work performed to date is in general conformance with the recommendations
contained in our referenced report, (GSI, 1997b), and with the grading ordinance of the
City of Carlsbad, California. Afinal compaction report of rough grading and improvements
construction, including observations and testing results for rough grading, utilities and
driveway/parking areas, is forthcoming. - The opportunity to be of service is greatly appreciated. If you have any questions, please
do not hesitate to call our office at (760) 438-31 55.
Respectfully submitted,
GeoSoils, Inc. A
Robert G. Crism
Project
RGCIDWSlhs
David W. Skelly
Civil Engineer, RCE 4
Distribution: (4) Addressee -
REFERENCES -
GeoSoils, Inc., 1997a, Foundation Design Recommendations Regarding Post-Tensioned
Slab Foundation Systems, Vistamar at San Pacifico, Carlsbad, California, W.O.
2198-A-SC, dated, May 12.
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-J 1997b, Geotechnical Review and Supplemental Geotechnical Evaluation, Vistamar - at San Pacifico, Carlsbad, California, W.O. 2198-A-SC, dated March 26.
L
GeoSoils, Ine.
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C 0 N S U L T A/N T S
July 8, 1997
J.N.: 93-1034
Mr. Tim Fennessey
City of Carlsbad
Engineering Department
2075 Las Palmas Drive
Carlsbad, CA 92009-1576
RE: POINSETTIA SHORES, AREA B-2, GRADING
PAD CERTIFICATION, C.P. 94-02
Dear Mr. Fennessey:
Based on our field survey on June 16, 1997, the rough grading for the pads of Dwg. No. 352-4A
have been substantially completed in accordance with the approved grading plan. The final
elevations and horizontal locations are certified to the approximate locations.
O’DAY SULTANTS, INC.
Patrick N. O’Day
President
PN0:th
cc: Mr. Jonathan Weldy, Watt Homes
7220Avenida Encinns Civil Engineering
Suite 204 I’limning
Carlsbad, California Y200Y Processing
619~932.7700 Snrveyins
Fnx: 619-931-8680
Watt Homes
June 18,1997
Mr. Tim Fennessy
Engineering Inspector
City of Carlsbad
2075 Las Palmas Drive
Carlsbad, CA 92009-1576
RE: Poinsettia Shores B-2 (Vistamar)
Grading Permit: GR 970013
CP 9402, DWG 352-4A
Dear Mr. Fennessy:
We would like to apply for a Partial Release of Rough Grading on the above-
referenced property for the following:
1. Retaining walls
2. Building pads
3. Streets
Please call me at (760) 603-9225 if you have any questions or need additional
information.
Sincerely,
Jerry Rice
Project Manager
GEOTECHNICAL REVIEW AND
SUPPLEMENTAL GEOTECHNICAL EVALUATION
VISTAMAR AT SAN PACIFIC0
CARLSBAD, CALIFORNIA
FOR
WAll HOMES
27720 JEFFERSON AVENUE, SUITE 200
TEMECULA, CALIFORNIA 92590
W.O. 2198-A-SC MARCH 26,1997
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.. . .. .. . -
~. ,. ., .. ,
Geotechnical Geologic Environmental
-
._
5741 Palmer Way Carlsbad, California 92008 * (619) 438-3155 * FAX (619) 931-0915
March 26, 1997
W.O. 21 98-A-SC
Watt Homes
Southern California Division
27720 Jefferson Avenue, Suite 200
Temecuia. California 92590
Attention:
Subject:
Ms. Carol Long, Mr. Jonathan Weldy
Geotechnical Review and Supplemental Geotechnical Evaluation, Vistamar
at San Pacifico, Carlsbad, California.
Dear Ms. or Sir.:
In accordance with your request, GeoSoils, Inc. (GSI) has reviewed the available
geotechnical reports and performed a geotechnical and geologic evaluation regarding
proposed development of the subject planning areas. The purpose of our study was to
evaluate the nature of earth materials underlying the site and to provide preliminary
recommendations for site preparation, earthwork construction, and foundation
design/construction, based on our findings. The subject study area, Vistamar at San
Pacifico, includes Areas 8-1, 8-2, and D of Poinsettia Shores Development.
EXECUTIVE SUMM ARy
Based on our review of the available data (Appendix A), field exploration, laboratory
testing, and geologic and engineering analysis, the proposed development appears to be
feasible from a geotechnical viewpoint, provided the recommendations presented in the
text of this report are properly incorporated into the design and construction of the project.
The most significant elements of this study are summarized below: . Soils unsuitable for the support of structures and/or compacted fill generally consist
of surficial fill and terrace deposits. Where observed, these materials are on the
order of 1 to 2 feet thick throughout the site. . Existing and proposed cut and fill slopes are considered to be generally stable,
assuming that these slopes are maintained and/or constructed in accordance with
recommendations presented in this report.
. Groundwater was not encountered in any of the excavations completed during site
work. However, perched groundwater conditions should not be precluded from
occurring in the future from site irrigation, poor drainage or damaged utilities. . Terrace deposits consisting of friable sands, or granular fills could be encountered
during utility trench construction. Precautions should be incorporated into the
construction of trenches into these materials, including, but not limited to: shoring,
or sloped excavations. . Based on the soil conditions observed, conventional foundation systems may be
The recommendations presented in this report should be incorporated into the
used to support structures.
design and construction considerations of the project. Previous recommendations
provided in Geocon (1994) and Leighton (1 995) have been reviewed, incorporated,
and/or modified as necessary in this report.
The opportunity to be of service is greatly appreciated. If you have any questions
concerning this report or if we may be of further assistance, please do not hesitate to
contact any of the undersigned.
.
Respectfully submitted,
Albert R. Kleist
J likGi2-2
Project Geologist, CEG 1929
RGC/ARWJRW/hs
Distribution: (10) Addressee
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TABLE OF CONTENTS
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SCOPE OF SERVICES ................................................... 1
SITE DESCRIPTION ..................................................... 1
PREVIOUS WORK ....................................................... 3
PROPOSED DEVELOPMENT .............................................. 3
FIELD EXPLORATION . '. .................................................. 4
EARTH MATERIALS ...................................................... 4
Artificial fill ....................................................... 4
Terrace Deposits .................................................. 4
Other Earth Materials ............................................... 4
SUBSURFACE WATER ................................................... 5
FAULTING AND REGIONAL SEISMICITY ..................................... 5
LABORATORY TESTING .................................................. 7
General .......................................................... 7
Moisture-Density Relations .......................................... 7
Expansion Potential ................................................ 7
Direct Shear Tests ................................................. 7
Sand Equivalent ................................................... 8
Corrosion Testing .................................................. 8
CONCLUSIONS ......................................................... 8
General .......................................................... 8
Earth Materials .................................................... 9
Existing Fill .................................................. 9
TerraceDeposits ............................................. 9
Slope Stability ..................................................... 9
Subsurfacewater ................................................. 10
SeismicHazards .................................................. 10
RECOMMENDATIONS-EARTHWORK CONSTRUCTION ....................... 10
GeneralGrading .................................................. 10
Site Preparation .................................................. 11
Removals ....................................................... 11
Fill Placement .................................................... 12
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Overexcavation ................................................... 12
Slopes .......................................................... 13
GradedSlopes ............................................. 13
Temporary Construction Slopes ................................ 13
FOUNDATION RECOMMENDATIONS ...................................... 13
General ......................................................... 13
Design .......................................................... 15
Lateral Pressure .................................................. 15
Foundation Settlement - Structural Loads .............................. 15
Foundation Construction ........................................... 16
Corrosion ....................................................... 16
Setbacks ........................................................ 16
Conventional Floor Slabs ........................................... 17
RETAINING WALLS ..................................................... 17
General ......................................................... 17
Restrained Walls .................................................. 18
Cantilevered Walls ................................................ 18
Wall Backfill and Drainage .......................................... 19
Retaining Wall Footing Transitions ................................... 19
PAVEMENTS ........................................................... 20
Preliminary Pavement Design ....................................... 20
Subgrade and Base Preparation ..................................... 21
Pavement Construction and Maintenance ............................. 21
DEVELOPMENT CRITERIA ............................................... 21
Landscape Maintenance and Planting ................................ 21
Exterior Flatwork .................................................. 22
Additional Site Improvements ....................................... 23
Additional Grading ................................................ 23
Footing Trench Excavation ......................................... 23
Trench Backfill ................................................... 23
PLAN REVIEW ......................................................... 24
LIMITATIONS .......................................................... 24
Bearingvalue .................................................... 15
Drainage ........................................................ 22
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FIGURES:
FIGURE1 ........................................................ 2
FIGURE2 ........................................................ 6
ATTACHMENTS:
APPENDIX A - References .................................. Rear of Text
APPENDIX B -Test Pit Logs ................................. Rear of Text
APPENDIX C - Laboratory Test Results ........................ Rear of Text
APPENDIX D - General Earthwork and Grading Guidelines ........ Rear of Text
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GeoSoils, he.
GEOTECHNICAL RNIEWAND
SUPPLEMENTAL GEOTECHNICAL NALUATION
VISTAMAR AT SAN PACINCO
CARLSBA D, CA LlFORNlA
GeoSoils, Inc. has provided the following services in preparation of this evaluation.
1.
2.
3.
4.
5.
6.
Literature research and review of available data, including published and
unpublished geologic and geotechnical reports and soils data for the area.
A visual reconnaissance of the site to evaluate existing surficial conditions, including
access, erosion, drainage, vegetation, etc.
Excavation of 13 exploratory test pits with a rubber tire backhoe to evaluate the
existing soil conditions.
Performance of laboratory testing for the determination of classification, compaction
(maximum dry density), density (unit weight), moisture content, direct shear
strength and pertinent engineering characteristics of selected materials, as deemed
necessary.
Analysis of data including general areal site seismicity, settlement, soil expansion
and soils engineering/earthwork with respect to the suitability for the proposed
residential development.
Preparation of this geotechnical report.
SITE DFSCRIPTION
Vistamar at San Pacific0 is comprised of planning Areas B-1 , 8-2 and D, formerly of the
Poinsettia Shores subdivision, in the City of Carlsbad, California (Figure 1). Areas B-1 and D are contiguous properties (totaling approximately 27 acres) located east of the San
Diego Northern Railroad easement, north and west of Avenida Encinias and south of an
existing mobile home community. Area B-2 (2.4 acres) is located southeast of areas B-l/D
and is bounded by Windrose Circle to the north, existing residential development to the
west and south, and vacant graded pads the east.
Topographically, Area 8-2 consists of four relatively flat-lying pads with intervening slopes
of 5 feet or less in height. Fill slopes, up to 5 feet in height, descend away from pad areas
around the perimeter of Area 8-2, toward Windrose Circle and Navigator Court. Site
drainage is directed from east to west within area 6-2. Area 6-1 is a relatively flat lying
sheet graded pad with minor slopes descending away from the pad to Avenida Encinas
and Area D. An existing cut slope, up to 20 feet in height, at a gradient of 2:1 (horizontal
CeoSoils, Inc.
2198-A-SC
0 1/2 1 N - Scale Miles
I SITE LOCATION MAP
Raproduced wlth permisslon ranted by Thmae BIOS. Yaps.
PerSOnai use or resale, without permidon. All rlghta rererved.
- Thia map ia copyrlghtmd by Tkames Broe. Maps. It Is unlawful to copy or reprodue. all or any part theroot. whether tor. Figure 1
10 feet. Planned graded fill slopes are anticipated to be less than 10 feet in height, at
gradients of 2:l or flatter. Proposed site development is shown on Plates 1 through 5.
Plates 1 through 5 use the 1"=40' scale tentative maps, prepared by O'day Consultants,
as a base.
D EXPLORAT ION
Subsurface conditions were explored for this study by excavating 13 test pits with a rubber
tire backhoe to depths ranging from 2% to 8 feet below existing grades. Logs of the test
excavations are included with this report in Appendix B. Field work was performed on
March 5, 1997 by a GSI geologist, who logged the excavations, obtained samples of
representative materials for laboratory testing and reviewed the site conditions. The
approximate locations of the test excavations are indicated on the enclosed Geotechnical
Maps (Plates 1 through 5).
EARTH MATFRWS
Earth materials encountered during field work consist of artificial fill and native soils
composed of Pleistocene-age terrace deposits.
Artifl cia1 fill lmaD svm bo1 a0
Existing artificial fill is distributed throughout all of the subject areas. Based on our review
of test pit data (this study) and a review of Leighton and Associates (1995), fills vary up to
12 feet in thickness within Area 8-2 and 10 feet within Area D and Area 8-1. Where
encountered in our exploratory test pits, artificial fill consists of dark yellowish brown silty
sand. In general, fill materials are slightly moist to moist and loose within 1 to 1 % feet of
existing grades. Below these depths, fill material is typically moist and medium dense.
Terra ce Deposits lmg@ sv mbol Q)
Pleistocene-age terrace deposits appear to underlie the entire site but are only observed
at existing grades within a portion of area 8-1. Where observed in our exploratory test pits,
these materials consist of yellowish brown silty sand and sand. Terrace deposits are
typically slightly moist to moist and medium dense. Silty sands are typically weakly
cemented while sands are friable. Some laminations observed within otherwise massive
terrace deposits, are weakly developed and generally subhorizontal to gently west sloping.
Other Earth Mat er ials
Sedimentary formational materials, belonging to the Eocene age Santiago Formation, were
noted in Geocon (1994) to underlie terrace deposits throughout the site. These materials
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were not encountered during our investigation and are not anticipated to affect planned
site development.
SUBSURFACE WATFR
Subsurface water was not encountered in any of the excavations for this evaluation. These
observations reflect site conditions at the time of our investigation and do not preclude
changes in local or perched groundwater conditions in the future from heavy irrigation,
precipitation, other factors not obvious at the time of our field work.
FAUl TlNG AND RFGIONAL SEISMICITY
No known active or potentially active faults are shown crossing the site on published maps
(Jennings, 1994). No evidence for active or potentially active faulting was encountered in
any of the exploratory excavations performed during this evaluation or in our referenced
report.
There are a number of faults in the Southern California area which are considered active
and would have an effect on the site in the form of ground shaking, should they be the
source of an earthquake. These include, but are not limited to: the San Andreas fault, the
San Jacinto fault, the Elsinore fault, the Coronado Bank fault zone and the Rose Canyon -
Newport-lnglewood (RCNI) fault zone. The approximate location of these and other major
faults relative to the site are shown .on Figure 2. The possibility of ground acceleration, or
shaking, at the site may be considered as approximately similar to the southern California
region as a whole.
The acceleration-attenuation relations of Joyner and Boore (1982) and Campbell et. al.
(1994) have been incorporated into EQFAULT (Blake, 1994). EQFAULT is a computer
program used for the deterministic evaluation of horizontal accelerations from digitized
California faults.
Peak horizontal ground site accelerations anticipated at the site were determined, based
on the attenuation relations indicated above. The largest probable and credible peak
horizontal ground accelerations anticipated at the site would range from 0.249 to 0.59 and
0.439 to 0.829 assuming maximum probable and credible events of magnitude 5.9 and
6.5, respectively, on the Rose-Canyon - Newport-lnglewood fault zone, located
approximately 6 miles west of the site.
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0 50 100 -
SCALE
(Miles)
FIGURE 2 \
W.O. 2198-A-SC
3/97
I AB ORATORY TFSTIN G
MAXIMUM
LOCATION SOIL NPE DENSITY
(PCFJ
General
Laboratory tests were performed on representative samples of the onsite earth materials
in order to evaluate their physical characteristics. The test procedures used and results
obtained are presented below.
OPTIMUM
MOISTURE
CONTENT (%)
Moisture-Density Relations
The laboratory maximum dry density and optimum moisture content for representative site
soils was determined according to test method ASTM D-1557-91. Results of this testing
are presented in the following table.
TP-1 @ 2'
TP-8 @ 3'
Reddish brown, silty SAND < 20 very low
reddish brown, silty SAND < 20 very low
ExDansion Po 'tential
Expansion index tests were performed on representative samples of site topsoil and
bedrock material in general accordance with Standard 18-2 of the Uniform Building Code.
Results are presented in the following table.
Direct Shear Tests
Shear testing was performed on remolded and undisturbed samples of site soil in general
accordance with ASTM Test Method D-3080. Test results are presented in the following
table.
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Sand EauivaleOf
Sand equivalent tests were performed in accordance with ASTM test method D-2419. The
results are presented in the following table.
,
LOCATION I SAND EQUIVALENT
TP-10 (composite) 21
TP-11 (composite) 26
Corrosion Testing
Corrosion testing of a representative sample of site soil was performed. The results of this
testing are presented in Appendix C.
CON CLUSI ONS
General
Based on our field exploration, laboratory testing and geotechnical engineering analysis,
it is our opinion that the site appears suitable for the proposed development from a
geotechnical engineering and geologic viewpoint, provided that the recommendations
presented in the following sections are incorporated into the design and construction
phases of site development. The primary geotechnical concerns with respect to the
proposed development are: . Depth to competent material. . Overexcavation of cut-fill transitions. . Potential for perched groundwater. . Friable nature of Terrace Deposits with respect to temporary and permanent
slope stability.
Additional conclusions regarding the site are presented in the following discussions.
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Earth Materials
Existing Fill
The results of density testing performed on existing compacted fill material are presented
on the test pit logs (see Appendix B). Based on a review of this data and laboratory
maximum dry density/optimum moisture content data presented within a previous section
of this report, the following conclusions are provided.
Existing compacted fill materials (map symbol a9 within areas B-1, 8-2 and D generally
appear to meet the current industry minimum standard of 90 percent (or greater) relative
compaction. However, our observations and testing indicates that the uppermost 1 foot
of fill soil is typically loose. This may be attributed to periodic drying and wetting since
placement.
Recommendations for the treatment of existing fills are presented in the earthwork section
of this report. Existing fill onsite is generally very low in expansive potential.
Terrace Deposits
Terrace deposits exposed in as-built cut areas of the sheet graded pads and underlying
existing fills are considered suitable for structural support. However, it should be noted
that relatively friable, cohesionless zones of sandy terrace deposits would be encountered
within existing cut areas of Area B-1. Special consideration will be required with respect
to the stability of planned and temporary cut slopes as well as trenching within these
materials and treated in accordance with recommendations contained in the earthwork
section of this report. Terrace deposits onsite are generally very low in expansive potential.
Slope StabiliQ
Based on our field investigations, laboratory testing and engineering analysis, existing
graded slopes, constructed during a previous phase of earthwork construction (Leighton,
1995) appear to be stable with respect to gross and surficial stability. Planned cut and fill
slopes, as planned, are also anticipated to be stable with respect to gross and surficial
stability provided that the slopes are constructed in accordance with the minimum
requirements of the County of San Diego, City of Carlsbad, the Uniform Building Code and
the recommendations presented in this report.
While existing and proposed slopes are, or anticipated to be stable, the exposed earth
materials at the slope face are considered erosive and should be protected appropriately.
Specific recommendations are presented within a later section of this report.
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Subsurface Wat er
Subsurface water, as discussed previously, is not anticipated to affect site development,
provided that the recommendations contained in this report are incorporated into final
design and construction and that prudent surface and subsurface drainage practices are
incorporated into the construction plans. Perched groundwater conditions along
fillherrace deposit contacts and along zones of contrasting permeabilities should not be
precluded from occurring in the future due to site irrigation, poor drainage conditions or
damaged utilities. Should perched groundwater conditions develop, this office could
assess the affected area@) and provide the appropriate recommendations to mitigate the
observed groundwater conditions.
Seismic Hazards
The following seismic related hazards have been considered during our evaluation of the
site. Based on our evaluation, these hazards are considered low and/or completely
mitigated as a result of site location, soil characteristics and typical site development
procedures: . Surface Fault Rupture . Ridge top shattering . Liquefaction . Tsunami
. Ground Lurching or Shallow Ground Rupture
However, it is important to keep in perspective that in the event of maximum probable or
credible earthquake occurring on any of the nearby major faults, intense ground shaking
would occur in this general area. Potential damage to any structures would likely be
greatest from the vibrations and impelling force caused by the inertia of a structure's mass,
than from those induced by the hazards considered above. This potential would be no
greater than that for other structures and improvements developed in the immediate
vicinity.
PEC OMMENDATIONS-F4RTHW ORK CONSTRUCTION
General Grading
The following recommendations presented below consider the conclusions discussed
above, as well as other aspects of the site (i.e., soil expansion, distribution of soil types,
soil strength, etc.). The engineering analyses performed concerning site preparation and
the recommendations presented herein, have been completed using the information
provided and obtained during our field work. In the event that any significant changes are
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made to proposed site development, the conclusions and recommendations contained in
this report shall not be considered valid unless the changes are reviewed and the
recommendations of this report verified or modified in writing by this office.
All grading should conform to the guidelines presented in UBC (1994) the requirements
of the City of Carlsbad, and Appendix D of this report, except where specifically
superseded in the text of this report. When code references are not equivalent, the more
stringent code should be followed.
During earthwork construction, all site preparation and the general grading procedures of
the contractor should be observed and the fill selectively tested by a representative(s) of
GSI. If unusual or unexpected conditions are exposed in the field, they should be reviewed
by this office and if warranted, modified and/or additional recommendations will be offered.
All applicable requirements of local and national construction and general industry safety
orders, the Occupational Safety and Health Act, and the Construction Safety Act should
be met.
Structures may be supported entirely on properly compacted fills or suitable native earth
material (terrace deposits). Building sites placed directly on terrace deposits should be
observed by the project geotechnical engineer or engineering geologist to verify
competent and consistent bearing materials are exposed. Based on the soil conditions
observed, conventional foundation systems may be used to support any proposed
structure.
Site PreDaration
Debris, vegetation and other deleterious material should be removed from the building
area prior to the start of construction. Sloping areas to receive fill should be properly
benched in accordance with our recommendations and guidelines specified in the UBC
(1 994).
Remova Is
Removals in areas to receive fill shall consist of all loose surficial fills and/or native soil.
Based on our subsurface exploration, removals are anticipated to be on the order of 1 to
2 feet below existing grades over a majority of the study area. However, deeper removals
may occur locally and should be anticipated, especially in the vicinity of the existing
desilting basins where removals may locally exceed 5 to 6 feet. Once removals are
complete, the area to receive fill should be scarified and moisture conditioned to a
minimum depth of 12 inches and compacted to a minimum 90 percent relative compaction.
Removals should be completed for a minimum lateral distance of 5 feet outside the
extreme exterior foundation elements for any structure or below a 1 :1 projection down and
away from the exterior foundation elements to the elevation of suitable material, whichever
is greater.
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It should be noted that in areas where removals are on the order of 1 foot (Area B-l), the
loose soils may be scarified, moisture conditioned and compacted in place.
Fill Plac ement
Subsequent to ground preparation, onsite soils may be placed in thin (6kinch) lifts,
cleaned of vegetation and debris, brought to a least optimum moisture content, and
compacted to achieve a minimum relative compaction of 90 percent.
If soil importation is planned, a sample of the soil import should be evaluated by this office
prior to importing in order to assure compatibility with the onsite site soils and the
recommendations presented in this report. Import soils should be relatively sandy with low
expansion potential (Le., expansion index less than 20).
Qverexcavation
Planned cut/fill transitions, juxtaposing existing and/or proposed fill against native soil are
anticipated to daylight at pad grade within building sites located in the vicinity of the
existing cut/fill transitions within Area 6-1. For uniform support, the cut portion of the pad
should be overexcavated in accordance with Table 1. Planned cut/fill transitions
juxtaposing existing and proposed fills are also anticipated. No special remedial treatment
of these conditions with respect to overexcavations are anticipated. However, removals
of existing loose surticial fill soils should be performed, as stated in a previous section.
MAXIMUM FILL DEPTH"'
(feet)
BEDROCK OVEREXCAVATION
(feet)
<IO
(')Fill depths as measured below grade within the building footprint.
@Overexcavations should be completed for a minimum lateral distance of 5 feet
outside the extreme exterior foundation elements for the structure, or below a 1:l
projection from the bottom outside edge of any settlement sensitive
improvements.
3
Based on our field exploration, and a review of Leighton (1995), overexcavations to 3 feet
below pad grade for all transition lots, are anticipated.
Areas where proposed fills are less than the recommended overexcavation depth should
be overexcavated in order to provide the recommended minimum fill blanket thickness.
Once overexcavations are completed, the exposed bottom should be scarified to a
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10-1 5 4
Once overexcavations are completed, the exposed bottom should be scarified to a
minimum depth of 8 inches, moisture conditioned, compacted and then brought to grade
with compacted fill.
SloDes
Graded Slopes
Proposed graded slopes may be constructed in accordance with the minimum
requirements of the County of San Diego, City of Carlsbad, the Uniform Building Code and
the recommendations presented in this report. Placement of an erosion control fabric
(e.g., jute netting), or similar protective system, over graded slope faces should be
considered in order to minimize erosion of the slope face until a suitable vegetation cover
is established. Slope terrace benches should be constructed in accordance with section
3315 of the Uniform Building Code (1994).
Temporary Construction Slopes
Temporary cuts for wall construction or removals/overexcavations should be constructed
at a gradient of 1 :1 or flatter. Construction materials and/or stockpiled soil should not be
stored within 5 feet of the top of any temporary slope. Temporary/permanent provisions
should be made to direct any potential runoff away from the top of temporary slopes.
Utility trenches constructed within terrace deposits and deeper than 4 feet, should be
constructed in accordance with guidelines presented in Title 8 of the California Code of
Regulations for Excavation, trenches and Earthwork with respect to Type "C" soil material.
Utility trenches constructed into existing or planned fills may be constructed in accordance
with guidelines for type "B soil material.
FOUNDATION RECWDA TIONS
General
In the event that the information concerning the proposed development plan is not correct,
or any changes in the design, location or loading conditions of the proposed structure are
made, the conclusions and recommendations contained in this report shall not be
considered valid unless the changes are reviewed and conclusions of this report are
modified or approved in writing by this office.
The information and recommendations presented in this section are not meant to
supersede design by the project structural engineer or civil engineer specializing in
structural design. Upon request, GSI could provide additional consultation regarding soil
parameters, as related to foundation design.
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to vertical) descends from the mobile home development along the northem property line
to the sheet graded pad. A fill slope, up to 10 feet in height, descends to area B-1 from an
adjacent sheet graded pad. Site drainage is generally directed to the northwest as sheet
flow. Area D is relatively flat-lying with site drainage directed to the north.
Existing improvements within the sheet graded pads consist of landscaping within existing
slope areas, and three desilting basins. One basin is located within each of the subject
areas at the following locations: within the western corner of Area 8-2 the northwestern
corner of Area B-1 , and the northern end of Area D.
PREVIOUS WORK
A previous preliminary geotechnical investigation for the Poinsettia Shores development
was issued on June 3,1994 by Geocon, Inc. This report presented findings of subsurface
exploration, engineering and geologic analysis, and laboratory testing, with conclusions
and recommendations regarding site development.
All of the subject planning areas have been sheet graded. The processing of original
ground and placement of compacted fill was performed under the observation and testing
services of Leighton and Associates, Inc. during the period from October, 1994 to October,
1995. A final as-graded report of rough grading was issued on October 20, 1995, by
Leighton and Associates.
Based on the findings presented in this report, and a review of Leighton and Associates
(1995), it appears that Area 8-2 and Area D are underlain by compacted fill while Area B-1
contains two cut/fill transitions which trend from south the north, across the central portion
of the property. The approximate location of these transitions are shown on the enclosed
Plates 1 through 5. Removals on the order of 4 to 7 feet appear to have been made prior
to fill placement. The maximum fill thickness was estimated, from the available literature,
and our field exploration to be 10 to 12 feet in the areas evaluated.
PROP OSED DEVEL OPMENT
Proposed development will consist of site preparation for the construction of 158 two-story
townhomes within Area B-1 , 16 two-story townhomes within Area B-2 and 29 townhomes
within Area D, including utilities and street improvements. It is our understanding that the
proposed structures would consist of one and/or two-story structures, with continuous
footings, and slabs-on-grade, utilizing wood-frame construction. Building loads area
assumed to be typical for these types of relatively light structures.
Cut and fill grading techniques are anticipated to be used to develop building site for the
planned structures and roadways. Planned cuts and fills are anticipated to be less than
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.-
columns. Differential settlement is not anticipated to exceed Vi inch between similar
elements, in a 20 foot span.
Foundation Construction
The following preliminary recommendations are for the proposed construction, in
consideration of our field investigation, laboratory testing and engineering analysis. These
construction recommendations are meant as minimums and are not intended to supersede
the recommendations of the structural engineer or corrosion specialist:
1. Due to the low expansive soil conditions identified onsite, foundations should be
constructed to a minimum depth of 12 inches below lowest adjacent grade.
Foundation widths may be constructed per UBC guidelines. All footings should be
minimally reinforced with four No. 4 reinforcing bars, two placed near the top and
two placed near the bottom of the footing.
Exterior post supports should be founded at a depth of 18 inches below the lowest
adjacent grade and tied to the main foundation system with a grade beam in two
directions. Reinforcement should be properly designed by the project structural
engineer.
A 12-inch wide grade beam, reinforced as above, and a minimum of 1 square foot
in cross section should be utilized across large entrances, such as garages or
double wide doorways. The base of the reinforced.grade beam should be at the
same elevation as the bottom of adjoining footings.
2.
Corrosion
The results of corrosion testing (see Appendix C) indicate that type 1/11 cement may be
used in foundation construction. Saturated resistivity is considered moderately corrosive,
therefore, consideration should be given to wrapping underground metallic piping. The
corrosion test results as well as utility foundation plans may be evaluated by a corrosion
specialist.
Setbacks
Foundations for any structure (including pools, tennis courts, etc.) should be setback from
the top of any adjacent descending slope, a distance equal to one-third the height of the
slope. This distance shall be no less than 7 feet and need not be greater than 40 feet.
Foundations for any adjacent structures, including retaining walls, should be deepened (as
necessary) to below a 1:l projection upward and away from any proposed lower
foundation system. This recommendation may not be considered valid, if the additional
surcharge imparted by the upper foundation on the lower foundation has been
incorporated into the design of the lower foundation.
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IlesklQ
Our field work and laboratory testing indicates that onsite soils are generally low in
expansion potential. Preliminary recommendations for foundation design and construction
are presented below based on the assumption that low expansive materials will be used
for support of structures. The foundation system should be designed and constructed in
accordance with the guidelines contained in the Uniform Building Code. Final foundation
designs should be based upon conditions exposed following earthwork construction.
Should higher expansive materials occur at pad grade, revised foundation
recommendations would need to be provided by GSI.
Bearina Val ue
1. Conventional spread and continuous strip footings may be used to support the
proposed structure, provided they are founded entirely in properly compacted fill.
An allowable bearing value of 2000 pounds per square foot should be used for
design of continuous footings 12 inches wide and 12 inches deep and for design
of isolated pad footings 24 inches square and 18 inches deep, entirely into
compacted fill or terrace deposits. This value may be increased by 400 pounds per
square foot for each additional 12 inches in depth to a maximum value of 2400
pounds per square foot. The above values may be increased by one-third when
considering short duration seismic or wind loads. No increase, in bearing, for
footing width is recommended. Residential footings should not simultaneously bear
directly on suitable native and fill soils.
2.
Lateral Pressure
1. Passive earth pressure may be computed as an equivalent fluid having a density of
225 pounds per cubic foot per foot of depth, to a maximum earth pressure of 2000
pounds per square foot.
An allowable coefficient of friction between earth material and concrete of 0.35 may
be used with the dead load forces.
When combining passive pressure and frictional resistance, the passive pressure
component should be reduced by one-third.
2.
3.
Foundation Settl ement - Structural Loads
Provided that the recommendations contained in this report are incorporated into final
design and construction phase of development, a majority (>50 percent) of the anticipated
foundation settlement is expected to occur during construction. Maximum settlement is
not expected to exceed approximately '/i inch and should occur below the heaviest loaded
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Additional setbacks, not discussed or superseded herein, and presented in the UBC are
considered valid.
Conventional F loor Slabs
Concrete slab on grade construction is anticipated. The following criteria are considered
minimum design parameters for the slab and they are in no way intended to supersede
design by the structural engineer. Slab criteria provided do not account for concentrated
loads from heavy machinery. Floors in slab areas are assumed to be designed for typical
residential floor slabs. Slabs subject to higher or concentrated loads (e.g., columns,
wails, etc.) should be properly designed by the project structural engineer.
The subgrade soil should be compacted to a minimum 90 percent of the laboratory
maximum density. Moisture conditioning is recommended for these soil conditions. The
moisture content of the subgrade soils should be equal to or greater than the soils
optimum moisture, to a depth of 18 inches below pad grade in the slab areas and verified
by this office within 48 hours of pouring slabs and prior to placing visqueen or
reinforcement.
Slabs should be a minimum of 4 inches thick and be minimally reinforced with No. 3
reinforcing bars on 18 inches centers both ways, or equivalent reinforcement. Reinforcing
should be properly supported on chairs or blocks to ensure placement near the vertical
midpoint of the slab. Concrete slab weakened plane or expansion joints should be placed
in accordance with current standards of practice and no greater than 12 feet apart.
Concrete slabs should be underlain with a minimum of 4 inches of sand. In addition,
where moisture condensation is undesirable, a vapor barrier consisting of a minimum 6 mil
thick, polyvinyl chloride or equivalent membrane, with all laps sealed, should be provided
at the mid-point of the sand layer. As an option, the lower 2-inch sand layer may be
omitted and the PVC membrane placed directly on the subgrade. provided the PVC
thickness is increase to a minimum of 1Omils.
General
Foundations may be designed using parameters provided in the "Design" section of
Foundation Recommendations presented herein. Wall sections should adhere to the
County of San Diego and/or City of Carlsbad guidelines. All wall designs should be
reviewed by a qualified structural engineer for structural capacity, overturning and stability.
The design parameters provided assume that onsite or equivalent low expansive soils are
used to backfill retaining walls. If expansive soils are used to backfill the proposed walls
within this wedge, increased active and at-rest earth pressures will need to be utilized for
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retaining wall design. Heavy compaction equipment should not be used above a 1 :1
projection up and away from the bottom of any wall.
The following recommendations are not meant to apply to specialty walls (cribwalls, loffel,
earthstone, etc.). Recommendations for specialty walls will be greater than those provided
herein, and can be provided upon request. Some movement of the walls constructed
should be anticipated as soil strength parameters are mobilized. This movement could
cause some cracking dependent upon the materials used to construct the wall. To reduce
wall cracking due to settlement, walls should be internally grouted and/or reinforced with
steel.
Restrained Walls
Any retaining walls that will be restrained prior to placing and compacting backfill material
or that have re-entrant or male corners, should be designed for an at-rest equivalent fluid
pressures of 60 pcf, plus any applicable surcharge loading. For areas of male or re-entrant
corners, the restrained wall design should extend a minimum distance of twice the height
of the wall laterally from the corner. Building walls below grade, should be water-proofed
or damp-proofed, depending on the degree of moisture protection desired. Refer to the
following section for preliminary recommendations from surcharge loads.
Cantilevered Walls
These recommendations are for cantilevered retaining walls up to 10 feet high. Active
earth pressure may be used for retaining wall design, provided the top of the wall is not
restrained from minor deflections. An empirical equivalent fluid pressure (EFP) approach
may be used to compute the horizontal pressure against the wall. Appropriate fluid unit
weights are provided for specific slope gradients of the retained material. These do not
include other superimposed loading conditions such as traffic, structures, seismic events
or adverse geologic conditions.
Level 35
2 to 1 I II
-
The equivalent fluid density should be increased to 65 pounds per cubic foot for level
backfill at the angle point of the wall (corner or male re-entrant) and extended a minimum
lateral distance of 2H (two times the wall height) on either side of the corner. Traffic loads -
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within a 1:l projection up from the wall heel, due to light trucks and cars should be
considered as a load of 100 psf per foot in the upper 5 feet of wall in uniform pressure. For
preliminary design purposes, footing loads within a 1 :1 backfill zone behind wall will be
added to the walls as 1/3 of the bearing pressure for one footing width, along the wall
alignment.
For earthquake loads (i.e., increase in active pressure) on the retaining wall due to the
acceleration of the backfill during seismic shaking, a seismic increment of 10H should be
added to the active wall pressures for level backfill. This value should be added as a
uniform pressure at and above a point equal to 0.6H, where H is the height of the backfill
behind the wall. For sloping backfill the seismic increment should be added as 15H for
slopes up to but not exceeding 2:l (horizontal to vertical).
Wall Backfill and Dra lnaae
All retaining walls should be provided with an adequate gravel and pipe backdrain and
outlet system (a minimum 2 outlets per wall), to prevent buildup of hydrostatic pressures
and be designed in accordance with minimum standards presented herein. Pipe should
consist of schedule 40 perforated PVC pipe. Gravel used in the backdrain systems should
be a minimum of 3 cubic feet per lineal foot of Ye- to 1%-inch clean crushed rock
encapsulated in filter fabric (Mirafi 140 or equivalent). Perforations in pipe should face
down. The surface of the backfill should be sealed by pavement or the top 18 inches
compacted to 90 percent relative compaction with native soil. Proper surface drainage
should also be provided.
As an alternative to gravel backdrains, panel drains (Miradrain 6000, Tensar, etc.) may be
used. Panel drains should be installed per manufacturers guidelines. Regardless of the
backdrain used, walls should be water proofed where they would impact living areas or
where staining would be objectionable.
Retaining Wall Footina Transitions
Site walls are anticipated to be supported on footings designed in accordance with the
recommendations in this report. Wall footings may transition from bedrock to fill. If this
condition is present the civil designer may specify either:
a) A minimum of a 2-foot overexcavation and recompaction of bedrock
materials, as measured for a distance of two times the height of the wall from
the transition in the direction of the wall. Overexcavations should be
completed for a minimum lateral distance of 2 feet beyond the footing,
measured perpendicular to the wall.
Increase of the amount of reinforcing steel and wall detailing (Le., expansion
joints or crack control joints) such that a angular distortion of 1/360 for a b)
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distance of 2H on either side of the transition may be accommodated.
Expansion joints should be sealed with a flexible grout.
Embed the footings entirely into native formational material. If transitions
from cut to fill transect the wall footing alignment at an angle of less than 45
degrees (plan view), then the designer should follow recommendation "a"
(above) and until such transition is between 45 and 90 degrees to the wall
alignment.
C)
TRAFFIC AREA
PAVEME NTS
AGGREGATE
TRAFFIC SUBGRADE W- THICKNESS THICKNESS '"
INDEX'" VALUE (inches) (inches)
kC. BASE
-
Prellminatv Pavement De S' Ian
Based on our general site observations and subsurface exploration, relatively sandy soils
are anticipated to be exposed at pavement subgrade within the site. Samples of
representative site soil were obtained and resistance ("R-Value") testing was performed.
Testing was performed in accordance with the latest revisions to the Department of
Transportation, State of California, Material & Research Test Method No. 301.
For general planning purposes, the following pavement sections are provided.
-
-
-
-
CUI Du Sac
Local Street
4.5 50 4.0 4.0
5.0 58 4.0 4.0
(1)
(2)
Denotes Class 2 Aggregate Base (R> 78, SE > 22).
Traffic Indices selected are estimates. -.
- Portland concrete cement (PCC) driveway pavement may be constructed to a minimum
thickness of 5 inches. All concrete pavement should be ASTM minimum 560-C-3250.
Concrete should be properly detailed in accordance with current industry standards and
- the Uniform Building Code.
Resistance value testing of actual subgrade during grading should be performed in order
to confirm or redefine R-values used in this report. If testing of actual subgrade determines
that the R-value is different than the assumed values presented herein, then the
-
-
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recommended pavement section must be revised. PCC pavement jointing should be
provided per county standards and no greater than 13 feet apart.
Subarade and Base Preparation
The upper 12 inches of subgrade should be scarified, moisture conditioned to at least
optimum moisture, and compacted to at least 95 percent of the maximum dry density.
Class 2 aggregate base should be compacted to at least 95 percent of its maximum dry
density. If adverse conditions (Le., saturated ground, etc.) are encountered during
preparation of the subgrade materials, special construction methods may need to be
employed.
Pavement Construc tion and &&&mme
The preliminary pavement sections are intended as minimums and should be verified with
“R-value testing of soils near final subgrade once grading is completed. If thinner or highly
variable pavement sections are constructed, increased maintenance and repair may be
needed.
Positive site drainage should be maintained at all times. Water should not be allowed to
pond or seep into the ground. If planters or landscaping are adjacent to paved areas,
measures should be taken to minimize the potential for water to enter the pavement
section. This may be accomplished using thickened PCC pavement edges, concrete cut
ofi’ barriers or deepened curbs.
DEVEL OPMENT CRITERIA
LandscaDe Maintena nce and Plan tiag
Water has been shown to weaken the inherent strength of soil, and slope stability is
significantly reduced by overly wet conditions. Positive surface drainage away from graded
slopes should be maintained and only the amount of irrigation necessary to sustain plant
life should be provided for planted slopes. Over-watering should be avoided.
Graded slopes constructed within and utilizing onsite materials would be potentially
erosive. Eroded debris may be minimized and suficial slope stability enhanced by
establishing and maintaining a suitable vegetation cover soon after construction. Plants
selected for landscaping should be light weight, deep rooted types which require little
water and are capable of surviving the prevailing climate. Compaction to the face of fill
slopes would tend to minimize short term erosion until vegetation is established. It order
to minimize erosion on the slope face, an erosion control fabric (i.e. jute matting) should
be considered.
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From a geotechnical standpoint, leaching is not recommended for establishing
landscaping. If the surface soils area processed for the purpose of adding amendments
they should be recompacted to 90 percent minimum relative compaction. Moisture
sensors, embedded into fill slopes, should be considered to reduce the potential of over-
watering from automatic landscape watering systems.
Drainaaa
Positive site drainage should be maintained at all times. Drainage should not flow
uncontrolled down any descending slope. Water should be directed away from
foundations and not allowed to pond andlor seep into the ground. Pad drainage should
be directed toward the street or other approved area. Roof gutters and down spouts
should be considered to control roof drainage. Down spouts should outlet a minimum of
5 feet from proposed structures or tightlined into a subsurface drainage system. We
recommend that any proposed open bottom planters adjacent to proposed structures be
eliminated for a minimum distance of 10 feet. As an alternative, closed bottom type
planters could be utilized. An outlet placed in the bottom of the planter, could be installed
to direct drainage away from structures or any exterior concrete flatwork. Drainage behind
top of walls should be accomplished length paved channel drainage v-ditch or substitute.
Exterior Flatwork
Exterior walkways, sidewalks, or patios, using concrete slab on grade construction, should
be designed and constructed in accordance with the following criteria.
1.
2.
3.
4.
Slabs should be a minimum 4 inches in thickness. A thickened edge should be
considered (12 inches in depth and 4 to 6 inches in thickness) for all flatwork
adjacent to landscape areas.
Slab subgrade should be compacted to a minimum 90 percent relative compaction
and moisture conditioned to at or above the soils optimum moisture content.
The use of transverse and longitudinal control joints should be considered to help
control slab cracking due to concrete shrinkage or expansion. Two of the best
ways to control this movement is; 1) add a sufficient amount of reinforcing steel,
increasing tensile strength of the slab, and/or 2) provide an adequate amount of
control and/or expansion joints to accommodate anticipated concrete shrinkage
and expansion. We would suggest that the maximum control joint spacing be
placed on 5- to 8-foot centers or the smallest dimension of the slab, whichever is
least.
No traffic should be allowed upon the newly poured concrete slabs until they have
been properly cured to within 75 percent of design strength.
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5. Positive site drainage should be maintained at all times. Adjacent landscaping
should be graded to drain into the street, parking area, or other approved area. All
surface water should be appropriately directed to areas designed for site drainage.
In areas directly adjacent to a continuous source of moisture (i.e. irrigation,
planters, etc.), all joints should be sealed with flexible mastic.
6.
If in the future, any additional improvements are planned for the site, recommendations
concerning the geological or geotechnical aspects of design and construction of said
improvements could be provided upon request this includes but not limited to appurtenant
structures, A/C support pads, pools and spas.
Additional Gra ding
This office should be notified in advance of any additional fill placement, regrading of the
site, or trench backfilling after rough grading has been completed. This includes any
grading, utility trench and retaining wall backfills.
Footina - Tren ch Fx cavatlon
All footing trench excavations should be observed and approved by a representative of this
office prior to placing reinforcement. Footing trench spoil and any excess soils generated
from utility trench excavations should be compacted to a minimum relative compaction of
90 percent, if not removed from the site. Trenches exposing sandy material can be
relatively unstable. Excavations exposing sandy soil should be observed by this office
prior to workers entering the excavation.
Trench Backfill
All excavations should be observed by one of our representatives and conform to
CAL-OSHA and local safety codes. Exterior trenches should not be excavated below a 1 :1
projection from the bottom of any adjacent foundation system. If excavated, these
trenches would undermine support for the foundation system potentially creating adverse
conditions.
1. All utility trench backfill in slopes, structural areas and beneath hardscape features
should be brought to near optimum moisture content and then compacted to obtain
a minimum relative compaction of 90 percent of the laboratory standard.
Observations, probing and, if deemed necessary, testing should be performed by
a representative of this office to verify compactive efforts of the contractor.
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2. Soils generated from utility trench excavations should be compacted to a minimum
of 90 percent if not removed from the site.
Jetting of backfill is not recommended.
The use of pipe jacking to place utilities is not recommended on this site.
Bottoms of utility trenches should be sloped away from structures.
3.
4.
5.
PLAN REVIEW
Final site development and foundation plans should be submitted to this office for review
and comment, as the plans become available, for the purpose of minimizing any
misunderstandings between the plans and recommendations presented herein. In
addition, foundation excavations and any additional earthwork construction performed on
the site should be observed and tested by this office. If conditions are found to differ
substantially from those stated, appropriate recommendations would be offered at that
time.
LI M lTATl0 NS
The materials encountered on the project site and utilized in our laboratory study are
believed representative of the area; however, soil and bedrock materials vary in character
between excavations and natural outcrops or conditions exposed during site grading and
construction. Site conditions may vary due to seasonal changes or other factors.
GeoSoils, Inc. assumes no responsibility or liability for work, testing or recommendations
performed or provided by others.
Since our study is based upon the site materials observed, selective laboratory testing and
engineering analysis, the conclusion and recommendations are professional opinions.
These opinions have been derived in accordance with current standards of practice and
no warranty is expressed or implied. Standards of practice are subject to change with
time.
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APPENDIX A
REFERENCES
ADDendix
REFERENCES
Blake, Thomas F., (1994) EQ FAULT Computer Program For The Deterministic Prediction
of Horizontal Accelerations From Digitized California faults.
Campbell, K.W. and Bozorgnia, Y., 1994, Near-Source attenuation of peak horizontal
acceleration from worldwide accelerograms recorded from 1957 to 1993;
Proceedings, Fifth U.S. National Conference on Earthquake Engineering, Vol. 111,
Earthquake Engineering Research Institute, pp. 293-292.
Geocon Incorporated, 1994, Geotechnical investigation for Poinsettia Shores, Carlsbad,
California, project no. 05318-12-01, dated June 3.
Jennings, C.W., (1994) Fault Activity Map of California, Scale 1:750,000, DMG Map No. 6.
Joyner, W.B, and Boore, D.M., 1982a, Estimation of response-spectral values as functions
of magnitude , distance and site conditions, in eds., Johnson, J.A., Campbell, K.W.,
and Blake, T.F.: AEG short course, seismic hazard analysis, June 18, 1994.
-, 1982b, Prediction of earthquake response spectra, in eds., Johnson, J.A., Campbell,
K.W., and Blake, T.F.: AEG short course, seismic hazard analysis, June 18, 1994.
Leighton and Associates, 1995, Final as-graded report of rough grading Lots 1 through 8,
Lot 79 and Unit 2, Poinsettia Shores, Carlsbad Tract 94-01, Carlsbad, California,
project no. 4940677-002, dated October 20.
Naval Facilities Engineering Command (NAVFAC), 1982, Soil mechanics design manual
7.1.
Naval Facilities Engineering Command (NAVFAC), 1982, Foundation design manual 7.2.
State of California, 1992, Construction Safety Orders, Sections 1504, 1539-1 547, Title 8,
California Code of Regulations, excavation, trenches, earthwork, March edition.
Uniform Building Code, 1994 Edition.
GeoSoils, Inc.
APPENDIX B
TEST PIT LOGS
NCI
9 m
I
>. a 0
a 0 J n X W
L 0 a 0
2
J
* K 0
U 0 J n x w
G
U 0 a 0 J
L
APPFNDIX C
LABORATORY TEST RESULTS
M. J. SCHIFF & ASSOCIATES, INC.
Consulting Corrosion Engineers - Since 1959 1291 Norlh Indian Hill Boulevard
Claremont. California 91711-3897
Phone 909-626-0967
FAX 909-521-1419
E-mail SCHIFFCORR@AOL.COM
Page 1 of 1 Table 1 - Laboratory Tests on Soil Samples
CeoSoik, Inc
Your #2198-A, MJS&A #97076
March 18,1997
Sample ID TP-IO
......... - .... ..... ...__
Soil Type silty
sand
Resistivity Units
as-received ohm-cm 8,700
saturated ohm-cm 3,400
PH 6.8
Electrical
Conductivity mSJcm 0.08
Chemical Analyses
Cations
calcium Ca2+ mgikg ND
magnesium Mg" mgikg ND
sodium Na" mgikg 95
bicarbonate HCO," mgikg 49
chloride CI'- mgikg 74
sulfate SO," mgikg 59
Anions
carbonate CO$ mgikg ND
Other Tests
sulfide S .?- qual na
Redox mv na
ammonium ",I+ mgkg na
na nitrate NO,'- mgikg ....... .... ,. ....
Electrical conductivity in millisiemendcm and chemical analysis are of a 1 :5 soil-to-water extract.
mgkg = milligrams per kilogram (parts per million) of dry soil.
Redox = oxidation-reduction potential in millivolts
ND = not detected
na = not analyzed
docs9A97076.slr
CORROSION AND CATHODIC PROTECTION ENGINEERING SERVICES
PLANS AND SPECIFICATIONS * FAILURE ANALYSIS ' EXPERT WITNESS * CORROSlVlPl AND DAMAGE ASSESSMENTS
R-VALUE DATA SHEET
W.O. 2198
PROJECT NUMBER 24464 BORING NUMBER: TP-1
SAMPLE DESCRIPTION: Brown Clayey Sand .....................................................................
itern SPECIMEN
Equilibrium R-value
-ransportation, State of California, Materials & Research Test Method No. 301.
-
R-VALUE GRAPHICAL PRESENTATION
- . 400 2 350
I 300
PROJECT NO. 2'.Iqb+
-1 96 ;fP- I W .- BORING NO. .. 0 21
PI
DATE 3-14-99 2 200
R-VALUE BY EXUDATION 50 20
W PI
PI 0 +
-
a 100 TRAFFIC INDEX
-
a E 0 V / R-VALUE BY EXPANSION -
800 700 600 500 400 300 200 100
100
90
80
70
60
50
40
30
20
10
0
1.0 2.0 3.0 4.0
COVER THICKNESS BY EXPANSION, ET. -
- loo r1.0
% MOISTURE AT FABRICATION
4.0
3.0
2.0
1.0
0
E
-
" - I R-VALUE VS. EXUD. PRES. I T by EXUDATION I I - ,.
A A A EXUD. T VS. EXPAN. T 4 A A T by EXPANSION -
REMARKS C= 1.25 -
APPEN DIX D
GENERAL EARTHWORK AND GRADING GUIDELINES
GENERAL EARTHWORK AND GRADING GUIDELINES
1. GENERAL
A. These guidelines present general procedures and requirements for earthwork and
grading as shown on the approved grading plans, including preparation of areas to filled, placement of fill, installation of subdrains and excavations. The
recommendations contained in the geotechnical report are part of the earthwork and grading guidelines and would supersede the provisions contained hereafter in the case of conflict. Evaluations performed by the consultant during the course
of grading may result in new recommendations which could supersede these
guidelines or the recommendations contained in the geotechnical report.
The contractor is responsible for the satisfactory completion of all earthwork in
accordance with provisions of the project plans and specifications. The project soil engineer and engineering geologist (geotechnical consultant) or their
representatives should provide observation and testing services, and geotechnical
consultation during the duration of the project.
8.
11. EARTHWORK OBSERVATIONS AND TESTING
A. Geotechnical Consultant
Prior to the commencement of grading, a qualified gec xhnical consultant (soil engineer and engineering geologist) should be employed for the purpose of observing earthwork procedures and testing the fills for conformance with the
recommendations of the geotechnical report, the approved grading plans, and applicable grading codes and ordinances.
The geotechnical consultant should provide testing and observation so that determination may be made that the work is being accomplished as specified.
It is the responsibility of the contractor to assist the consultants and keep them apprised of anticipated work schedules and changes, so that they may schedule
their personnel accordingly.
All clean-outs, prepared ground to receive fill, key excavations, and subdrains
should be observed and documented by the project engineering geologist andlor soil engineer prior to placing and fill. It is the contractor’s responsibility to notify
the engineering geologist and soil engineer when such areas are ready for observation.
General Earthwork and Grading Guidelines Page 2
8.
C.
Laboratory and Field Tests
Maximum dry density tests to determine the degree of cornpaction should be
performed in accordance with American Standard Testing Materials test method
ASTM designation D-1557-78. Random field compaction tests should be performed in accordance with test method ASTM designation D-1556-82, D-2937 or D-2922 and D-3017, at intervals of approximately two (2) feet of fiil height or every 100 cubic yards of fill placed. These criteria would vary depending on the soil conditions and the size of the project The location and frequency of testing would be at the discretion of the geotechnical consultant.
Contractor’s Responsibility
All clezring, site preparation, and earthwork performed on the project should be conducted by the contractor, with observation by geotechnical consultants and staged approval by the governing agencies, as applicable. It is the contractor’s responsibility to prepare the ground surface to receive the fill, to the satisfaction
Of the soil engineer, and to place, spread, moisture condition, mix and compact
the fill in accordance with the recommendations of the soil engineer. The
contractor should also remove all major non-earth material considered unsatisfactsry by the soil engineer.
It is the sole responsibility of the contractor to provide adequate equipment and
methods to accomplish the earthwork in accordance with applicable grading
guidelines, codes or agency ordinances, and approved grading plans. Sufficient
watering apparatus and compaction equipment should be provided by the
contractor with due consideration for the fill material, rate of placement, and Climatic conditions. If, in the opinion of the geotechnical Consultant, unsatisfactory conditions such as questionable weather, excessive oversized rock, or deleterious
material, insufficient support equipment, etc.. are resulting in a quality of work that
is not acceptable, the consultant will inform the contractor, and the contractor is expected to recbfy the conditions, and if necessary, stop work until conditions are satisfactory.
During construction, the contractor shall properly grade all surfaces to maintain
good drajnage and prevent ponding of water. The contractor shall tzke remedial
measures to control surface water and to prevent erosion of graded areas until such time as permanent drainage and erosion control measures have been installed.
..
- General Earthwork and Grading Guidelines Page 3
SITE PREPARATION
All major vegetation, including brush, trees, thick grasses, organic debris, and
other deleterious material should be removed and disposed of off-site. These
removals must be concluded prior to placing fill. Existing fill, soil, alluvium,
colluvium, or rock materials determined by the soil engineer or engineering
geologist as being unsuitable in-place should be removed prior to fill placement.
Depending upon the soil conditions, these materials may be reused as compacted
fills. Any materials incorporated as part of the compacted fills should be approved
by the soil engineer.
Any underground structures such as cesspools, cisterns, mining shafts, tunnels,
septic tanks, wells, pipelines, or other structures not located prior to grading are
to be removed or treated in a manner recommended by the soul engineer. Soft,
dry, spongy, highly fractured, or otherwise unsuitable ground extending to such
a depth that surface processing cannot adequately improve the condition should
be over-excavated down to firm ground and approved by the soil engineer before
compaction and filling operations continue. Overexcavated and processed soils
which have been properly mixed and moisture conditioned should be re-
compacted to the minimum relative compaction as specified in these guidelines.
=sting ground which is determined to be satisfactory for support of the fills
should be scarified to a minimum depth of six (6) inches or as directed by the soil
engineer. After the scarified ground is brought to optimum moisture content or
greater and mixed, the materials should be compacted as specified herein. If the
scarified zone is grater that 6 inches in depth, it may be necessary to remove the
excess and place the material in lifts restricted to about six (6) inches in
compacted thickness.
Existing ground which is not satisfactory to support compacted fill should be over-
excavated as required in the geotechnical report or by the on-site soils engineer
and/or engineering geologist. Scarification, disc harrowing, or other acceptable
form of mixing should continue until the soils are broken down and free of large
lumps or clods, until the working surface is reasonably uniform and freP from ruts,
hollow. hummocks. or other uneven features which would inhibit compaction as ~. ~ ~ described in Item 111, C. above.
L
General Earthwork and Grading Guidelines Page 4
\fmms\grJd~a.lrm\495 -
E.
F.
G.
IV.
A.
B.
Where fills are to be placed on ground with slopes steeper than 5:l (horizontal to vertical), the ground should be stepped or benched. The lowest bench, which will act as a key, should be a minimum of 15 feet wide and should be at least two (2) feet deep into firm material, and approved by the soil engineer and/or engineering
geologist. In fill over cut slope conditions, the recommended minimum width of the lowest bench or key is also 15 feet with the key founded on firm material, as designated by the Geotechnical Consultant. As a general rule, unless specifically recommended otherwise by the Soil Engineer, the minimum width of fill keys
should be approximately equal to one-half (1/2) the height of the slope.
Standard benching is generally four feet (minimum) vertically, exposing firm, acceptable material. Benching may be used to remove unsuitable materials,
although It is understood that the vertical height of the bench may exceed four
feet. Pre-stripping may be considered for unsuitable materials in excess of four
feet in thickness.
All areas to receive fill, including processed areas, removal areas, and the toe of
fill benches should be observed and approved by the soil engineer and/or engineering geologist prior to placement of fill. Fills may then be properly placed and compacted until design grades (elevations) are attained.
COMPACTED FILLS
Any earth materials imported or excavated on the property may be utilized in the
fill provided that each material has been determined to be suitable by the soil
engineer. These materials should be free of roots, tree branches, other organic matter or other deleterious materials. All unsuitable materials should be removed
from the fill as directed by the soil engineer. Soils of poor gradation, undesirable
expansion potential, or substandard strength characteristics may be designated
by the consultant as unsuitable and may require blending with other soils to serve as a satisfactory fill material.
Ell materials derived from benching operations should be dispersed throughout
the fill area and blended with other bedrock derived material. Benching Operations should not result in the benched material being placed only within a single equipment width away from the fill/bedrock contact.
..
General Earthwork and Grading Guidelines Page 6
Where tests indiczte that the density of any layer of fill, or portion thereof, is below
the required relative cornpaction, or improper moisture is in evidence, the
particular layer or portion shall be re-worked until the required density and/or
moisture content has been attained. No additional fill shall be placed in an area
until the last placed lift of fill has been tested and found to meet the density and
moisture requirements, and is approved by the soil engineer.
Compaction of slopes should be accomplished by over-building a minimum of
three (3) feet horizontally, and subsequently trimming back to the design slope
configuration. Testing shall be performed as the fill is elevated to evaluate
compaction as the fill core is being developed. Special efforts may be necessary
to attain the specified compaction in the fill slope zone. Final slope shaping
should be performed by trimming and removing loose materials with appropriate
equipment. A final determination of fill Slope compaction should be based on
observation and/or testing of the finished slope face. Where compacted fill slopes
are designed steeper than 23 (horizontal to vertical), specific material types, a
higher minimum relative compaction, and special grading procedures, may be
recommended.
If an alternative to over-building and cutting back the compacted fill slopes is
selected, then special effort should be made to achieve the required compaction
in the outer 10 feet of each lift of fill by undertaking the following:
1) An extra piece of equipment consisting of a heavy short shanked sheepsfoot
should be used to roll (horizontal) parallel to the slopes continuously as fill is
Placed. The sheepsfoot roller should also be used to roll perpendicular to the
slopes, and extend out over the slope to provide adequate compaction to the face
of the slope.
2) Loose fill should not be spilled out over the face of the slope as each lift is
Compacted. Any loose fill spilled over a previously completed slope face should
be trimmed off or be subject to re-rolling.
3) Field compaction tests will be made in the outer (horizontal) two (2) to eight
(8) feet of the slope at appropriate vertical intervals, subsequent to compaction
operations.
H.
I.
General Earthwork and Grading Guidelines Page 5
c. Oversized materials defined as rock or other irreducible materials wiih a maximum
dimension greater than 12 inches should not be buried or placed in fills unless the
location of materials and disposal rne?hods are specifically approved by the soil engineer. Oversized material should be taken oii-site or placed in accordance
with recommendations of the soil engineer in areas designated as suitable for rock
disposal. Oversized material should no be placed within 10 feet vertically of finish
grade (elevation) or within 20 feet horizontally of slope faces.
To facilitate future trenching, rock should not be placed within the range of
foundation excavations, future utilities, or underground construction unless
specifically approved by the soil engineer and/or the developer’s representative.
If import material is required for grading, representative samples of the materials
to be utilized as compacted fill should be analyzed in the laboratory by the soil
engineer to determine its physical properties. If any material other than that
previously tested is encountered during grading, an appropriate analysis of this
material should b conducted by the soil engineer as soon as possible.
Approved fill material should be placed in areas prepared to receive fill in near
horizontal layers that when compacted should not exceed six (6) inches in
thickness. The soil engineer may approve thick lifts if testing indicates the grading
procedures are such that adequate compaction is being achieved with lifts of
greater thickness. Each layer should be spread evenly and blended to attain
uniformity of material and moisture suitable for compaction.
Fill layers at a moisture content less than optimum should be watered and mixed,
and wet fill layers should be aerated by scarification or should be blended with
drier material. Moisture condition, blending, and mixing of the fill layer should
continue until the fill materials have a uniform moisture content at or above
optimum moisture.
After each layer has been evenly spread, moisture conditioned and mixed, it
should be uniformly compacted to a minimum of 90 percent of maximum density
as determined by ASTM test designation. D 1557-78, or as otherwise
recommended by the soil engineer. Compaction equipment should be adequately
sized and should be specifically designed for soil compaction or of proven
reliability tc efficiently achieve the specified degree of compaction.
D.
E.
F.
G.
General Earthwork and Grading Guidelines Page 7
V.
VI.
A.
8.
4) After completion of the slope, the slope face should be shaped with a small
tractor and then re-rolled with a sheepsioot to achieve cornpaction to near the
slope face. Subsequent to testing to verij compaction, the slopes should be
grid-rolled to achieve compaction to the slope face. Final testing should be usEd
to confirm compaction after grid rolling.
5) Where testing indicates less than adequate compaction, the contractor will be
responsible to rip, water, mix and re-compact the slope material as necessary to
achieve compaction. Additional testing should be performed to verij compaction.
6) Erosion control and drainage devices should be designed by the project civil
engineer in compliance with ordinances of the controlling governmental agencies,
and/or in accordance with the recommendation of the soil engineer or engineering
geologist.
SUBDRAIN INSTALLATION
Subdrains should be installed in approved ground in accordance with the
approximate alignment and details indicated by the geotechnical consultant.
Subdrain locations or. materials should not be changed or modified without
approval of the geotechnical consultant. The soil engineer and/or engineering
geologist may recommend and direct changes in,subdrain line, grade and drain
material in the field, pending exposed conditions. The location of constructed
subdrains should be recorded by the project civil engineer.
MCAVATIO NS
Excavations and cut slopes should be examined during grading by the
engineering geologist. If directed by the engineering geologist, further
excavations or overexcavation and re-filling of cut areas should be performed
and/or remedial grading of cut slopes should be performed. When fill over cut
Slopes are to be graded, unless otherwisa approved. the cut portion of the Slope
should be observed by the engineering geologist prior to placement of materials
for construction of the fill portion of the slope.
The engineering geologist should observe all cut slopes and should be notified
by the contractor when cut slopes are started.
C.
D.
E.
VII.
A.
B.
C.
General Earthwork and Grading Guidelines Page 8
If, during the course of grading, unforeseen adverse or potential adverse geologic
conditions are encountered, the engineering geologist and soil engineer should
investigate, evaluate and make recommendations to treat these problems. The
need for cut slope buttressing or stabilizing should be based on in-grading
evaluation by the engineering geologist, whether anticipated or not.
Unless otherwise specified in soil and geological reports, no cut slopes should be
excavated higher or stegper than that allowed by the ordinances of controlling
governmental agencies. Additionally, short-term stability of temporary cut slopes
is the contractor’s responsibility.
Erosion control and drainage devices should be designed by the project civil
engineer and should be constructed in compliance with the ordinances of the
controlling governmental agencies, and/or in accordance with the
recommendations of the soil engineer or engineering geologist.
COMPLETION
Observation, testing and consultation by the geotechnical consultant should be
conducted during the grading operations in order to state an opinion that all cut
and filled areas are graded in .accordance with the approved project
specifications.
After completion of grading and after the soil engineer and engineering geologist
have finished their observations of the work, final reports should be submitted
subject to review by the controlling governmental agencies. No further excavation
or filling should be undertaken without prior notification of the soil engineer and/or
engineering geologist.
All finished cut and fill slopes should be protected from erosion and/or be planted
in accordance with the project specifications and/or as recommended by a
landscape architect. Such protection and/or planning should be undertaken as
Soon as practical after completion of grading.
General Earthwork and Grading Guidelines Page 9
-
VIII. JOB SAFEIY
A. General
At GeoSoils, Inc. (GSI) getting the job done safely is of primary concern. The following
is the company’s safety considerations for use by all employees on multi-employer construction sites. On ground personnel are at highest risk of injury and possible fatality on grading and construction projects. GSI recognizes that construction activities will vary on each site and that site safety is the a responsibility of the contractor; however, everyone must be safety conscious and responsible at all times. To achieve our goal of avoiding accidents, cooperation between the client, the contractor and GSI personnel must be maintained.
In an effort to minimize risks associated with geotechnical testing and observation, the following precautjons are to be implemented for the safety of field personnel on grading and construction projects:
1. Safetv Meetinas: GSI field personnel are directed to attend contractor’s regularly scheduled and documented safety meetings.
Safetv Vests: Safety vests are provided for and are to be
worn by GSI personnel at all times when they are working in the field.
Safetv Flaas: Two safety flags are provided to GSI field
technicians; one is to be affixed to the vehicle when on site, the other is to be placed atop the spoil pile on all test pits.
Flashina Liahts: All vehicles stationary in the grading area
shall use rotating or flashing amber beacon, or strobe lights, on the vehicle during all field testing. While operating a
vehicle in the grading area, the emergency flasher on the
vehicle shall be activated.
In the event that the contractor’s representative observes any of our personnel not following the above, we request that it be brought to the attention of our office.
2.
3.
4.
General Earthwork and Grading Guidelines Page 10
6.
The technician is responsible for selecting test pit locations. A primary concern should be the technician’s safety. Efforts will be made to coordinate locations with the grading
contractor’s authorized representative, and to select locations following or behind the established traffic pattern. preferably outside of current traffic. The contractor’s
authorized representative (dump man, operator, supervisor, grade checker, etc.) should
direct excavation of the pit and safety during the test period. Of paramount concern
should be the soil technician’s safety and obtaining enough tests to represent the fill.
Test pits should be excavated so that the spoil pile is placed away form oncoming traffic, whenever possible. The technician’s vehicle is to be placed next to the test pit, opposite
the spoil pile. This necessitates the fill be maintained in a driveable condition.
Alternatively, the contractor may wish to park a piece of equipment in front of the test holes, particularly in small fill areas or those with limited access.
A zone of non-encroachment should be established for all test pits. No grading
equipment should enter this zone during the testing procedure. The zone should extend
approximately 50 feet outward from the center of the test pit. This zone is established
for safety and to avoid excessive ground vibration which typically decreased test results.
Test Pits Location, Orientation and Clearance
When taking slope tests the technician should park the vehicle directly above or below the test location. If this is not possible, a prominent flag should be placed at the top of the slope. The contractor’s representative should effectively keep all equipment at a Safe operation distance (e.g. 50 feet) away from the slope during this testing.
The technician is directed to withdraw from the active portion of the fill as soon as possible following testing. The technician’s vehicle should be parked at the perimeter
Of the fill in a highly visible location, well away from the equipment traffic pattern.
The Contractor should inform our personnel al all changes to haul roads, cut and fill areas or other factors that may affect site access and site safety.
In the event that the technician’s safety is jeopardized or compromised as a result of the
contractor’s failure to comply with any of the above, the technician is required, by company policy, to immediately withdraw and notify hidher supervisor. The grading contractor’s representative will eventually be contacted in an effort to effect a solution.
However, in the interim, no further testing will be performed until the situation is rectified.
Any fill place can be considered unacceptable and subject to reprocessing.
recompaction or removal.
General Earthwork and Grading Guidelines Page 11
In the event that the soil technician does not comply with the above or other established
Safety guidelines, we request that the contractor bring this to hidher attention and notify
this office. Effective communication and coordination between the contractor's
representative and the soils technician is strongly encouraged in order to implement the
above safety plan.
C. Trench and Vertical Excavation
It is the contractor's responsibility to provide safe ~CCESS into trenches where compaction
testing is needed.
Our personnel are directed not to enter any excavation or vertical cut which 1) are 5 feet
or deeper unless shored or laid back, 2) displays any evidence of instability, has any
loose rock or other debris which could fall into the trench, or 3) displays any other
evidence of any unsafe conditions regardless of depth.
All trench excavations or vertical cuts in excess of 5 feet deep, which a persons enters,
should be shored or laid back.
Trench access should be provided in accordance with OSHA andor State and local
standards., Our personnel are directed not to enter any trench by being lowered or
"riding down" on the equipment.
If the contractor fails to provide safe access to trenches for compaction testing, our
company policy requires that the soil technician withdraw and notify his/her supervisor.
me contractor's representative will eventually be contacted in an effort to effect a
solution. All backfill not tested due to safety concerns or other reasons could be subject
to rePrOCeSSing and/or removal.
If GSI personnel become aware of anyone working beneath an unsafe trench wall or
Vertical excavation, we have a legal obligation to put the contractor and owner/develoPer
On notice to immediately correct the situation. If corrective steps are not taken, GSI then
has an obligation to notify CAL-OSHA and/or the proper authorities.
CANYON SUBDEAIN DETAIL
i
FROPOSEP COMPACTEJ ZLL /’
/’
\ \
CANYON SUBDRAIN ALTEZNATE DETAILS
ALTESNATE 1: PEsFOEATEg FIFE AND FILTEF MATE3lAL
FILTER MATERIAL: MINIMUM VOLUME OF S FT.'
/LINEAR FT. 6' a ABS OR PVC PIPE oi?
* SUBSTITUTE WIT4 MINIMUM 8 ItlL'~1 LINEAR FT. IN BOTTOM HALF OF PIF,. ASTM 02751. SOR 35 OR ASTM 01527. SCHO. LO ASTM 0303L, SCIR 35 OR ASTM 01785. SCKO. LO FOR CONTINUOUS RUN IN EXCESS OF 500 FT. USE 6.d PIPE
6-1 A-1
FILTER SlFVE 5175
1 INCH 31L INCH
318 INCH NO. L NO. 8 -NO. 30
. NO. 50 NO. 200
MATERIAL PERCENT PASSING
100 90-100 LO-100
25-LO 18-33
6-15 0--I 0--3
ALTERNATE 2: PE&CORP;TED PIPE. GRAVEL AND FILTEZ FABRIC
OVERLAP 6' MINIMUM OVESLAP -2
6' MINIMUM COYER
-L' MINIMUM BEOGING L' MINIMUM
A-2 GZAVEL'MAERIAL 9 FT'ILINEAR FT. 8-2
PE.FORATE3 PIPE: SEE ALTERNA'TE 1
GZAVEL CLEAN 3/ L INCA ROC( OR APPROVE3 SUBST[wE
FILES FAGRIC: MIRAFI 1LO OR APPROVE3 SUGSTITUTE
PLATE EG--2
DETAIL FOR FILL SLOPE TOEING OUT
ON FLAT ALLUVIATED CANYON
T .- IL= Cc SLCFE AS SSOWN CN GZAOING FLAN \
ORIGINAL GSOUNO SURFACE TO EE SE-CTOREZ WlTii COMPACTES FiLL
FJR OEE.? REMOVALS.
EACKCUT 'h\SHOULD CE MAOE NO
ANTICIPATE2 ALLUVIAL REMOVAL
OE'TH FE3 SaIL EHGINEE.?.
STEE'E2 THA%:1 OR AS NECESSARY /\ / " CONSIOEEATIONS
-------
'OR 7 / \\ '
PROJECTION F2OM TOE OF
SLOPE AS SHOWN ON GRAOING FLAN TO THE RECOMMENDED REMOVAL OEPTH. SLOPE HEIGHT. SITE COHOITIONS ANOlOR
LOCAL COtii3iTIOH-C COULD DICTATE FLATTEn' PROJECTIONS.
REMOVAL ADJACENT TO EXISTING FILL
ADJOINING CANYON FILL
PLATE EG-3
-
PLATE EG-k
v,
1 6
>- I-
-
r PLATE EG--r!
N
- - c
W 0
>- W v-
e
PLATE EG-5
W
I- 3 0
E W > 0
n
I
PLATE EG-7
LLI n 0 1 m
I- 3 0
LL 0
7 0. F cc 0 Q
7
Q W m 0 n X W
-
..
PLATE EG-8
<
c c 0
- L - -
I- < i -
Ir 0 -
PLATE EG-9
\
\
PL4TE EG-70
TEANSITiON LOT DETAIL
CUT LOT (MATEZIIAL TYFE TZANSITlONI
ATYPICAL EENCHING ///,N
PLATE EG-11
OVERSIZE ROCK OISPOSAL
NOTE:
~ ~~ ~~~ ~ ~~
' ONE EQUIPMENT WIOTH OR A MINIMUM OF 15 FEET. (81 HEIGHT AN0 WIOTH MAY VARY OEPENOING ON ROCK SEE AN0 TYPE OF EQUIPMENT USED. MAXIMUM.
IC] IF APPROVED gy THE SOILS ENGINEER ANOlOR ENGlNEEilNG GEOLOGIST. WINOROWS MAY BE PLACE0 DIRECTLY ON COMPETENT MATERIALS OR 6EJROC.Y
PROWOE0 AOEQUATE SPACE IS AVAILABLE FOR COMPACTION.
(01 ORIENTATION OF WINOROWS MAY VARY 8UT SHALL 6E AS RPCOMNENOED BY THE SOILS ENGINES9 ANOlOR EHGINE3ING GEOLOGIST. STAGGEAING OF WINDROWS IS NOT NECESSARY UNLESS RECOMMENDED. (€1 CLEAR AREA FOR UTILJTY TRENCHES. FOUNDATIONS AN0 SWIMMING POOLS. IF] VOIPS IN WINOROW SHALL 5E FILLECl E?' FLOOOING GZANULAR SOIL INTO PLACE- GXANULAR SOIL SHALL aE ANY SOIL WHICH HAS A UNlFiECl SaIL CLASSlECATION SYSTEM lUBC 29-11 OESIGNATION OF SM. Sa=, 5';;. :,=, C? rd.
AN0 AROUNO ROCK WINOROW SHALL EE COMPACTEO TO 9O%GELATlVC
LENGTH OF WINOROW SiiALL 6E NO GREATEX TdAN 100'
ALL ELL 0'fE.F
COMPACTION.
(GI AFTEi! FiLL SETWEEN WINOROWS IS ?LACE2 AN0 COMPACTS3 WIT6 T%E LIFT
OF FILL COVESING WINOROW. WINCROW SSALL 2: PROOF EOLLCZ 'NITii A E-?
OOZE.? OR EQUIVAENT. .- (HI OVE?SlZE,z EOCK IS OEZNEZ AS LAZG? TYAN 12: AN0 LE:: TSAN L .-==: -- - -
ROCK DISPOSAL PITS
FILL LIFTS COMFACTE.~ OVEZ
GZANULAR MATE.?IAL
ZOCK AFTEZ E96E5MENT
r------
I
1 7
I
I
I I
I I
I SQE OF EXCAVATION TO EE C'MHENSURATE I
I WITH ROCK SEE. I I I I
I I
---------
I COMPACTED FILL
NOTE: 1. LARGE ROCK 1s OE~NED AS ROCK LARGER THAN L FEET IN MAXIMUM 5iiE.
2. PIT IS EXCAVATEJ INTO COMPACTED FILL TO A OEITH E.3UAL TO 112 OF
ROCK SGE.
2. GRANULAR SOIL S?OULO 5E FUSHECI INTO PIT AN0 OENSlFlE3 EY FL0001NG.
L. A MINIMUM OF L FEET OF REGULAR COMPACTED FILL SSOULO OVEELIE
USE A SilEE'S;;OT AROUNO ROCK TO AI0 IN COHFACTION.
EACH PIT.
5. PITS SHOULD EE SEFARATECI 6Y AT LEAST 15 FEET HORIZONTALLY.
5. PITS SZOULO NOT SE PLACELI WITHIN 20 FEET OF ANY FiLL SLOPE.
'. SHOULD ONLY CE USEO IN OEEI FILL AREAS.
PLATE EG--13
=,,,NOARO -- 1 z/L. PIFS NIF,=LE 'fIEtZEJ TO Tor'
OF FLATE.
3IL' X S'GALVANIZEJ PIPE. STANOAZG FIFE
THREADS TOF AN0 EOTTOM. EXTENSIONS
THREAOEO ON EOTH ENOS AN0 AOOEO IN 5'
INCRS ME NTS.
3 INCH SCHEDULE LO PVC PIFE SLEEVE. A00 IN
S'INCREMENTS WITH GLUE JOINTS.
FINAL GRAOE
MAINTAIN 5'CLEARANCE OF HEAVY EOUIPMENT.
*MECHANICALLY HANO COMPACT IN 2'VERTICZ.L
-
R ALTERNATIVE SUITABLE TO AN0 3 EY THE SO115 ENGiNEEZ.
-
MECHANICALLY HANO COMPACT TiiE INITIAL 5'
VERTICAL WITHIN A S'GAOIUS OF PLATE EASE.
-
\ \
-
-
OM OF CLEANOUT
PROVIOE A MINIMUM 1' SEOOlNG OF COMPACTED St40 -
NOTE:
-- . .... - I-.I, APPROVE0 RY T
iHOULO EE CLEARLY MARKEO AN0 READlLY
TYPICAL SURFACE SETTLEMENT MONUMENT
FINISH GRAOE
3''
f-
- 3f8' OIAMETE3 X 6' LENGTH
CARRIAGE BOLT OR EQUIVALENT
I--B'OIAMETER X 3 1/2'LENGTH HOLE
CONCRETE BACKFlLL
PLATE EG--15
TEST PIT SAFETY DIAGRAM
( NOT TO SCALE 1
( NOT TO SCALE 1
PLATE EG-16
OVEF?SIZE ROCK DISPOSAL
VIEIN NORMAL TO SLOFE FACE
VIEW PARALLEL TO SLOPE FACE
PROPOSE9 FiNISH GZAOE
~1O'MlNlMUH (El .
15' MINIMUM
NOTE: (AI (51
IC1
101
(El
( il
ONF F~IIIIPMFNT winw OR A MINIMUM OF 15 FEET. - . . - - - - . . . . - . . , . . ._ . . . . HEIGHT AN0 WlOTH MAY VARY OEFENDING ON ROCK SIZE AN0 TYPE OF
EaUIPMENT.
IF APPROVED 2Y THE SOILS ENGINEE? ANOlOR ENGlNEE?ING GEOLOGIST.
WINOROWS MAY eE FLACEJ DIRECTLY ON COMPZTENT MATE?lAL OR EEORocx FRO'flOEO AOE.2UATE SiACE IS AVAILABLE FJR COMPACTION.
ORIENTATION 0.K WINOROWS MAY VARY E!UT SiiOULD BE AS RECOHMEHOEO E'!
LENGTH OF WINDROW SHALL EE NO Gi?EATER THAN IOO'MAXIMUM
THE SOlLS -.._...--- emus~~==~ ANOlOR ENGINEZ~ING GEJLOCIST. sTAGGE~ING OF
WINOROWS I5 t!CT ::E',E5SARY UNLESS RECOMMEHOEO. CLEAR AREA FJ~ UTILITY TRE?!CHES. FJUNOATIONS ANO S;VIMMING iOOLS.
ALL FILL OVER AN0 AROUNO ROCK WINOROW WALL %E C3MPACTEO TO 90%
-7ELATlVE COM?ACTION OR AS RECOMMENOEO. (GI AFTER FILL SETWEIN WINOROWS IS PLACE; AN0 COMPACTE3 WITH THE LIFT OF FILL COVERING WINOROW. wlNOGOW SSOUL? EE .?DOOF XCILLEZ WIT'+ A